For side window roll-up shades of motor vehicles, the current trend is to hide as much as possible the guide devices which guide movement of the roll-up shade during extension. Thus, guide rails, which have been used up until now and which extend at the side of the rectangular part of the window, must be replaced by guide or support rods. When the shade is in an extended position, the support rods, as their name suggests, support the pull rod attached to the free edge of the roll-up shade material. Thus they assume two functions: to guide the pull rod in such a way that it remains on the window, and to generate the necessary pushing force to keep the roll-up shade material unwound from the wind-up shaft and under tension. In the retracted state, the support rods disappear within the interior of the door body and are not visible.